Flood chaos in Philippines after deadly typhoon

Tens of thousands of people in the Philippines are battling neck-deep floodwaters in the chaotic aftermath of a ferocious typhoon that claimed at least 23 lives.

Typhoon Nesat slammed into the main island of Luzon before dawn on Tuesday, dumping enormous amounts of rain over the area that is home to 48 million people, before moving into the South China Sea on Wednesday.

As some areas on the outskirts of capital Manila were deluged with floods up to 1.5 metres deep, authorities sent out boats to rescue people stranded on the roofs of their houses.

One of the worst affected areas was Bulacan province, an hour's drive north of the capital, where dykes burst and water was released from dams that reached critical levels during the height of Tyhphoon Nesat's fury.

"Two of my sons are stranded, they texted me that they spent last night on the roof," security guard Resty Tolentino said as he waded through murky waters in a bid to reach his home in Calumpit.

He and another son struggled with the strong current in the waist-deep water while carrying food and other supplies.

The capital was brought to a near standstill during the height of the typhoon with dramatic storm surges in Manila Bay that crashed over seawalls, flooding a hospital, a five-star hotel and the US embassy.

Two of my sons are stranded, they texted me that they spent last night on the roof.

Calumpit resident Resty Tolentino

The death toll rose to 23 on Wednesday from 16 overnight, with another 35 people missing.

However most of the newly reported deaths were due to landslides in the mountainous regions of the northern Philippines, and not the flooded areas in or near the capital.

Authorities say their top priority is to help those stranded in flooded villages and to repair damaged infrastructure in Manila before more bad weather strikes.

"We are focusing on trying to get power and telecommunications services today, and work crews have also fanned out to repair and clear 61 road networks across Luzon," civil defence chief Benito Ramos said.

He says more than 1 million people remained without power on Wednesday in Manila and seven outlying provinces.